This revision proposes to develop innovative technology to continuously monitor the distances between 6 multiple identified individuals with a large, 75-85 member, rhesus monkey group. A primary specific aim of 7 MH050268 is to monitor the social behavior of rhesus monkeys who received complete ibotenic acid-induced 8 lesions of the amygdala at 30 days of age in comparison to comparable control monkeys. Delineating patterns 9 of social affiliation in group living rhesus monkeys is a very labor intensive enterprise. This results in 10 collecting relatively brief samples of behavior from direct observation, 40 mins of focal observations per animal 11 per week in the case of MH050268. We will develop a system that simultaneously tracks the precise locations 12 of multiple individuals continuously in our subjects'half acre living area. Distance between individuals is a key 13 diagnostic for social affiliation. We propose to infer affiliative relationships from knowing the relative distance 14 between individuals and the times spent at different distances. Monkeys are rarely within 12cm of each other 15 by accident, thus knowing the amount of time spent at that distance allows us to infer affiliative patterns and 16 compare them between lesioned and control animals. The proposed system uses infrared (IR) transponders 17 attached to primate collars that are polled by a transmission system in each compound. When the transmitter 18 polls an individual's IR transponder it emits a brief IR pulse. Multiple high speed IR cameras which cover the 19 1/2 acre area, detect the IR flashes. Since the transmitter knows which IR transponder was polled it knows the 20 identity of the animal sending the IR flash. The system polls all of the IR transponders in sequence 60 times/ 21 second allowing capture of extremely precise location information of all monkeys carrying the IR transponders. 22 Subsequent software processing of this location information with innovative software developed under this 23 proposal will allow reconstruction of the patterns of affiliation throughout the day. When implemented, this 24 system will allow the collection within a week, assuming 56hr of data/animal/week, of data that would currently 25 require almost 85 weeks of focal animal samples to collect. This high rate of data capture allows us to sample 26 subjects much more intensely than is currently feasible and will significantly enhance data collection in this 27 study allowing us to meet our specific aims in a much more comprehensive manner than currently possible. In 28 addition this system, by capturing data on multiple animals simultaneously, will significantly enhance our 29 ability to describe the social context of affiliative behavior in a manner that is impossible with focal sample 30 techniques. PUBLIC HEALTH RELEVANCE: This project develops innovative new technology that will automate the continuous collection of social interaction data in complex social groups of monkeys. Delineating patterns of social affiliation in group living rhesus monkeys is a very labor intensive enterprise. We propose to develop a system that simultaneously tracks the precise locations of multiple individuals continuously in large social groups of monkeys in their half acre living area. We can infer affiliative and other social relations by simply knowing the relative location of individuals and the times spent at different distances. We will employ this technology to evaluate the patterns of social interaction in the amygdalectomized and control rhesus monkeys created under the parent R01, dramatically increasing the amount and type of social behavioral data we can collect. These data will potentially reveal social deficits that would remain undetectable by traditional observation methods.